Organic solvent based polyester resins have been used in a variety of applications, including coatings, paints, adhesives, and the like. Many organic solvents commonly used in conjunction with such polyester resins present environmental problems associated with their toxicity. There has been a growing interest in the use of aqueous based polyester compositions as a means of eliminating toxicity problems and complying with certain government standards and regulations.
Various water dispersible polyester resins are known in the art. U.S. Pat. No. 4,179,420 discloses water dispersible oil-modified polyesters and oil-free polyesters which are formed by the reaction of aromatic dicarboxylic acids, aliphatic dicarboxylic acids, and polyols. This reference indicates that maleic anhydride or trimellitic anhydride can be used to form polyesters which can become water-soluble with the polyesters produced from these reactants being rendered water-soluble by the aid of an amine, a metal oxide, hydroxide or carbonate. U.S. Pat. Nos. 4,304,900 and 4,304,901 relate to linear water dissipatible polyesters and polyester amides which contain a disulfonamido compound and a sulfonic acid salt moiety, respectively, in order to render them water-dissipatible.